81316317 has 16 divisors (see below), whose sum is σ = 112159232. Its totient is φ = 52349760.

The previous prime is 81316283. The next prime is 81316349. The reversal of 81316317 is 71361318.

It is not a de Polignac number, because 81316317 - 2¹⁰ = 81315293 is a prime.

It is a super-2 number, since 2×81316317² = 13224686820888978, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81316357) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81063 + ... + 82059.

It is an arithmetic number, because the mean of its divisors is an integer number (7009952).

Almost surely, 2^81316317 is an apocalyptic number.

It is an amenable number.

81316317 is a deficient number, since it is larger than the sum of its proper divisors (30842915).

81316317 is a wasteful number, since it uses less digits than its factorization.

81316317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1908.

The product of its digits is 3024, while the sum is 30.

The square root of 81316317 is about 9017.5560436296. The cubic root of 81316317 is about 433.2373593503.

The spelling of 81316317 in words is "eighty-one million, three hundred sixteen thousand, three hundred seventeen".